Adhesive compositions are used to bond glass (windows) into building and vehicles, see Rizk, U.S. Pat. No. 4,780,520; Bhat, U.S. Pat. No. 5,976,305; Hsieh et al, U.S. Pat. No. 6,015,475 and Zhou, U.S. Pat. No. 6,709,539, all incorporated herein by reference. In automobile factories windows are installed using robots and computer controlled processing which facilitates the use of a variety of high performance adhesives, for instance nonconductive adhesives and high modulus adhesives. The speed of cure is not a significant issue because new vehicles are not driven a significant distance for several days after window installation. When a vehicle needs a window replaced, it is often performed in a remote location by an installer working at the vehicle to be repaired. In this environment, speed of cure is important as the vehicle owner desires to drive the vehicle as soon as possible after installation of the window. Adhesives useful in replacing windows for vehicles which facilitate fast drive away times are known as Bhat, U.S. Pat. No. 5,976,305 and Zhou, U.S. Pat. No. 6,709,539. The introduction of various high performance adhesive compositions used for installing windows in automobile factories presents a problem for replacement window installers. First, adhesives that meet all the varied performance requirements are not available in the market place. Second, it is difficult to formulate many high performance adhesive compositions to allow rapid drive away times that do not sag or string. Sag is the loss of the shape of the adhesive bead, often as the result of gravitational forces. If severe enough, this, deformation can interfere in the proper installation and sealing of the window on the vehicle. Stringing of an adhesive is the formation of a long string of adhesive at the end of the bead after dispensing which can complicate application and cause imperfections in the installed adhesive bead. Replacement window installers often carry a variety of adhesives to match the adhesive to the properties of the original adhesive used.
Isocyanate functional adhesives are utilized for bonding glass into structures and contain plasticizers to adjust the rheology and dispensability of these adhesives. Typically, plasticizers used in isocyanate functional adhesives were adopted initially from plasticizers developed for use in polyvinyl chloride plastisol compositions because of their cost and availability. One common class of plasticizers used in isocyanate functional adhesives are alkyl phathates. Such compounds, to date, have been available and cost effective. Recently, however, EH&S concerns have been raised about these materials negatively impacting the cost and availability. There is a need to find new plasticizers for isocyanate functional adhesives.
What is needed is a composition which is useful as an adhesive for bonding glass into a structure which may be formulated to exhibit a variety of high performance properties (such as high modulus and nonconductive nature), exhibits fast safe drive way times when applied under a variety of conditions, fast strength development, can be applied without the need for heating the adhesive, can be applied under a wide range of environmental conditions, does not requite expensive ingredients, can be applied to glass without the need for a primer and does not sag or string when applied. Compositions containing plasticizers adapted for use with isocyanate functional adhesives having low viscosities, desirable polarity, high boiling points, low volatility, derived from renewable resources are needed.